aarch64: signal not working for go runtime

[shrik3]

reported #1217 (comment)

I think the issue is that the current sig delivery is not dealing with user custom stack correctly (that was set by sys_sigaltstack)

[mhomidi]

Hi @shrik3,

The issue is that we do not need to reset registers in the this line qlib/kernel/threadmgr/task_signals.rs:1313. Just uncomment this and everything works.

After seeing the go-runtime source code, I figured out that they read the address of g from some of these register we made them zero. So, the issue comes from it because the register point to g is pointing to null.

[shrik3]

Hi @shrik3,

The issue is that we do not need to reset registers in the this line qlib/kernel/threadmgr/task_signals.rs:1313. Just uncomment this and everything works.

After seeing the go-runtime source code, I figured out that they read the address of g from some of these register we made them zero. So, the issue comes from it because the register point to g is pointing to null.

thanks for figuring out the problem! This makes sense. However I'm not sure whether we should leave the saved trap frame (spelt pt_regs) totally as is. I'll look into linux signal handling later.

(and why should that differ from x86? how does go runtime find the g there?)

[shrik3]

should be fixed by #1326 , reopen should other related issues emerge.